Elon Musk will be back on Tesla’s assembly line this month

The CEO wrote in an email to staff Thursday that he will walk the entire Model 3 production line on Nov. 27 and 28. From battery cells to finished vehicles, all assembly areas need to be able to support making 1,000 cars per day, Musk said.

“If you can’t see a way to get there, please let me know as soon as possible, so that I can help solve for this outcome,” Musk wrote in the email. “This is extremely important for our prosperity.”

The email shows Musk, 47, continues to cast himself for a hands-on role in boosting the number of batteries and cars Tesla can manufacture. Production progress was a major factor in the company’s surprise third-quarter profit, as higher output enabled Model 3 to became one of the top-selling sedans in the U.S. market.

Musk said during an earnings call last month that he saw a path to manufacturing 7,000 Model 3s per week with minimal capital expenditures, but didn’t give a time frame for when the company would achieve that rate.

“Last quarter was great, but now we need to prove financial sustainability,” Musk wrote in a separate email to staff. Tesla needs to produce 1,000 Model 3s a day on a sustained basis in the next few weeks to achieve “a financially healthy quarter,” and then the company will keep increasing output in early 2019 as it starts shipments to Europe and Asia, he said.